title: A comparative study of F-18 FDG PET and 201Tl scintigraphy for detection of primary malignant bone and soft-tissue tumors.
abstract: OBJECTIVE
  The purpose of this study was to compare 2-[F-18]fluoro-2-deoxy-D-glucose (FDG) positron emission tomography (PET) and Tl-201 chloride (Tl) scintigraphy for detection of primary malignant bone and soft-tissue tumors.
  
  
  METHODS
  A total of 40 patients with suspicion of malignant bone and soft-tissue tumors were examined. FDG PET imaging was performed at 1-hour post-FDG injection. Tl planar and single photon emission computed tomography images were acquired 10 minutes (early) and 2 hours (delayed) after injection of Tl. We evaluated FDG and Tl uptake visually and semiquantitatively using standardized uptake value and tumor to contralateral normal tissue ratio on planar images, respectively.
  
  
  RESULTS
  Of the 33 patients with malignant tumors, all but 2 liposarcomas showed positive accumulation on FDG PET. However, all 7 benign lesions were also positive on FDG PET. Both early and delayed Tl images were positive for 27 of the 33 malignant tumors. Of the 6 false-negative cases on Tl images, 5 were liposarcomas. Both early and delayed Tl images were negative for 5 of the 7 benign lesions. The sensitivity of FDG PET for detection of primary malignant bone and soft-tissue tumors was 94% and the specificity, 0%. The corresponding values for Tl scintigraphy were 82% and 71%. The mean FDG standardized uptake value in malignant tumors was higher than that in benign lesions, but this difference was not statistically significant. Statistically significant differences were observed between malignant and benign lesions for both early and delayed tumor to contralateral normal tissue ratios.
  
  
  CONCLUSIONS
  FDG PET was found to be more sensitive than Tl scintigraphy for primary malignant bone and soft-tissue tumors, although it was less specific.
authors.affiliation: Department of Radiology, Faculty of Medicine, Kagawa University, Kagawa, Japan. yuka@kms.ac.jp
authors.forename: Yuka
authors.initials: Y
authors.lastname: Yamamoto
authors.forename: Yoji
authors.initials: Y
authors.lastname: Kawaguchi
authors.forename: Yoshiro
authors.initials: Y
authors.lastname: Kawase
authors.forename: Yukito
authors.initials: Y
authors.lastname: Maeda
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Nishiyama
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001859:Bone Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D002648:Child; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008297:Male; D008875:Middle Aged; D049268:Positron-Emission Tomography / Q000379:methods*; D011859:Radiography; D012189:Retrospective Studies; D012983:Soft Tissue Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D013794:Thallium Radioisotopes; D055815:Young Adult
chemical_list: D013794:Thallium Radioisotopes; D019788:Fluorodeoxyglucose F18